Cisco Systems is planning to ship a wireless VoIP phone for Wi-Fi networks in June. The phone — the Cisco 7920 — uses only 802.11b networks and is designed for use within enterprises rather than totally replacing a cell phone. Cisco, however, is also reputed to be in talks with handset makers about the possibility of adding cell phone capability to such a device, which might carry the Cisco brand. The 7920 joins Cisco’s 7960 IP phone, which sits on a desk and plugs into a wired Ethernet network, and brings the added benefit of mobility around a building or campus that has a wireless LAN.